Apparatus for cracking hydrocarbons



y1920 zu@ Au 9 l1927.

g G EGLOFF ErAL APPARATUS FOR CRACKING HYDROCARBONS Original Filed Dec.23.

Patented Aug. 9, 1927.

- UNITED STATESv 1,638,116 PATENT OFFICE.

GUSTAV EGLOFF AND JOSEPH G. ALTHER, OF CHICAGO, ILLINOIS, ASSIGNORS T0UNI- VERSAL OIL PRODUCTS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OFSOUTH DAKOTA.

APPARATUS-FOR CRACKING HYDROCARBONS.

' Application led December 23, 1920, Serial No. 432,847. Renewed March24, 1927.

This invention relates to an improvement in an apparatus for crackinghydrocarbons and refers more particularly to anapparatus in which theheat generated is economically used to heat the raw oil and the raw oilused to dephlegmate and condense the generated vapors. f

Among the salient objects'of the invention are to provide an apparatus,different por-- tions of Which are maintained under differentialpressures and one in which subsequent to the cracking or releasing ofthc generated vapors, they are dephlegmated by being passed -in'closerelation to the incoming raw oil and thereby fractionally condensed; Atoprovide an apparatus in which the vapors, after being fractionallycondensed, are finally condensed in a multi-Whirl condenser in which thecool raw oil is circulatcd'about the uncondensed vapors, ytaking uptheir heat and causing them to be liqueiedinto a distillate: to providean apparatus whereby the heat ot the residuum is transferred to aportion of the incoming raw oil by circulating the latter about tubes inwhich the residuum is contained, and to provide an apparatus in whichregulated quantities of' the raw Voil, and the reliuX condensate arecharged to the heating tubes for treatment.

4The figure is a side4 levation, partly m section, of the apparatus.-

Referring in detail to the' drawings-heating tubes 1 are mounted in a.furnace 2, preferably heated by means of gas burner 3. At

' 4 is.- an expansion chamber connected to the 5in which,l

cracking tubesby means of aline is interposed'the yvalve 6. At 7 1s areflux condenser of' -the 4 multi-Whirl ltype connected y to theexpansion chamber bythe vapor line8 controlled by a valve 9.. A vaporline 1() from the top of the reflux condenser directs the uncondensedvapors to a condenser 11 similarly constructed on, the multi-whirlprinciple, Which is connected to` av receiver A12 by means of the: pipe13. A- raw o1l prethe raw oil by means of the hot residuum drawn fromthe expansion chamber through lthe line l5 controlled by a valve- 16 islikewise built on the multi-whirl principle. In operating thisapparatus, the raw oilis introduced from any convenient source (notshown) through the pump 17, charging pipe 18 controlled by a. valve 19to the multi-Whirl the top of the condenser the raw oil passes through aline 22 to the top of the vreflux condenser 7 where it circulates aboutthe vertical tubes 23 arranged therein, subjectmg the generated vaporsto a fractional -condensing action due tothe fact that the raw oil is ata lower temperature than the vapors contained in the vertical tubes.In'the reflux condenser 7 the course of the raw oil is identical to thatin the condenser 11 except that the oil flows from the top to thelbottom of the reflux'condenser as contrasted With its lopposed directionof flow in the'condenser.l

On reaching the bottom of the reflux condenser, the preheated raw oilcharge is drawn ofi' through the pipe 24 controlled by a valve 25, whichcommunicates with the reflux line .'26. leading back to the crackingtubes 1. In 'this line is interposed a valve 27. After be- -ing heatedto a cracking temperature in the heating tubes, the oil charge,comprising raw oil and whatever reflux 1s added from the reflux llnes,passes over to the expansion chamber Where it is vaporized under a.substantial pressure of the generated vapor. The released vapors passoff through the vapor line 8, any condensate forming 1n the vapor lineio'wing with the reflux back to the heatin tubes. The oil vapors, on theother han rise through the lvertical tubes 23 in the r'ellux condenserand, after being cooled by the cooler raw oil circulated about thevertical tubes on the spiral baille 28, pass ofi' through the vapor line10 to the condenser 11. -There lheater 14 adapted to preheat a. portionof( the vapors pass through the vertical tubes 'pressure gauge 29 andliquid level gauge 30,

besides having a pressure relief pipe 31 controlled b a valve 32 andliquid draw-off 33 regulate by a Valve 34.

It is obvious, of course, that the raw oil and the vapors are kept outof contact in both the reflux condenser and the final condenser and theheat transfer taking place slowly through radiation. At both ends of thereflux condenser and the final condenser are enlarged chambers intowhich the' vertical pipes lead.

Returning now to utilizing the heat from the residuum drawn 0H from theexpansion chamber, a multi- Whirl preheater or 'residuum cooler 14' o fsimilar construction to both the reflux condenser and final condenser`is connected to the residuum draw-ofi' in the expansion chamber. Byintroducing raw oil from t-he same, 'or a like source, as that fromwhich the raw oil lthrough the pump 17 is obtained and charging it tothe lower portionof the resi-duum cooler` through a pump 35 and line 36controlled by a valve 37 and causing it to circulate upward in' a spiralcourse about the vertical tubes 38 in which the hot residuum is causedto flow, this portion of the raw oil absorbs considerable heat from thehot residuum. The preheated oil, after its forced circulation about thehot residual oil, is drawn off through the pipe 39 regulated by a valve40 and introduced. into the combination reflux and charging line 26 in yregulated quantities.

In efficiently operating this apparatus, the heating coil may bemaintained at a temperature of 850 F.'and under a pressure ofapproximately 250 pounds or thereabouts.

,The temperature in the expansion chamber.

would approximate 745 F while that in the reflux condenser would rangefrom 700 to 400 Rand, after being introduced to the final condenser, thetemperature wouldl be reduced substantially lower than" the'end pointofthe .distillate collected i in the receiver. vThe raw oil beingintroducedat from 60475" F., according to at- Inospheric conditions, issubjected to the temperatures previously mentioned inthe condenser andreflux condenserand is flux after receiving an additional quantity ofpreheated raw oil from the residuum cooler. The apparatus affords anopporthe apparatus. for

tunity for utilizing a greater amount of the heatgenerated in thecracking or heating zone, the greater part of which has heretofore beenpermitted to be dissipated into the atmosphere. Further, by use of'circulating mediums, such las raw oil, about the condensing andrefluxing stages of the apparatus, a more accurate regulation and a moredirect control of the temperatures may be obtained. i

We claim as our invention:-

1. In an apparatus for cracking hydrocarbon oils, the combination with afurnace, of a cracking coil therein, an expansion chamber adjacent saidcoil into which oil is delivered, a reflux condenser, means for passinggenerated vapors to said refiux condenser, means for feeding chargingstock to the reflux condenser to condense the heavier insufficientlycracked vapors, means for discharging residual oil from saidn expansionchamber, a preheater receiving said oil, means for feeding anindependent supply of charging stock to said preheater, and means forintroducing "the heated charging stock from the preheater and the refluxcondensate and charging stock from the reflux condenser to said crackingcoil.

2. In an apparatus for cracking hydrocarbon oil, the combination with afurnace, a cracking coil therein, an enlarged expansion chamber adjacentsaid'coil, means for introducing4 heated oil to said chamber where -asubstantial portion 'of the oil va denser, means for feeding chargingstock to the reflux condenser, means forv returning condensate andpreheated charging stock to the cracklng coil, means for withdrawingresidual oil from the expansion chamber, a

preheater receiving said oil, separate means for feeding an independentsupply of raw` oil to said preheater, and means for admitting saidindependent supp1y,of preheated raw oil to the cracking coil with thereflux condensate and charging stock passing from the reflux condenser.

'crusfrav7 EGLoFF. JOSEPH e. ALTHER.

